The Guyhirn couple found themselves targeted by a thief at 3.45am when an alarm went off and the woman ran to the window to see him at work.

She banged on the window and the man, described as being 5ft 5in with a slim build and dark hair, ran off.

“We later found he had attempted to steal over 350 litres of heating oil from our tank using professional tools to cut through the hinges of a lock that was attached to the oil tank,” said the housewife.

The stolen heating oil was later recovered by the couple in their garden, where it appears the thief abandoned it after being disturbed. Eight full 25 litre barrels were found, along with six empty barrels.

Her husband said: “It was really nerve-wracking at the time, I’m in a wheelchair, so I had to wake my wife when the alarm went off and get her to go and look through the window at the tank.”

A spokesman for BoilerJuice, a UK on line supplier, said: “The couple had heard rumours of thefts in the area but this is the first time they have fallen victim to the crime. In addition to replacing the broken tank lock, they now plan to install further security measures, including security lighting and CCTV. “

The spokesman said: “Heating oil is a valuable commodity, with the average 1,000 litre order currently costing around £513.

“If thieves target your tank it can be a huge blow to your finances.”

To find out more about how you can protect your oil tank, visit www.BoilerJuice.com or call 0800 321 3275.